What is the difference between asexual cells and sexual cells

That is the main difference between sexual and asexual reproduction. Sexual reproduction just means combining genetic material from two parents. Asexual reproduction produces offspring genetically identical to the one parent

Simplistic term Answer - Difference between Asexual and Sexual is

Asexual does not need a mate. For example a hydra or a star fish which they can split their body and self regenerate into both halves with two star fish full regenerated.

Sexual has to have either an internal fert. or external fert. with a needed partner. Just like us humans a female reproductives and males sperm to create a another scary living.